Walter scott



(N0 Model.)

W. SCOTT. Rotary Engine.

No. 234,206. Patented Nov. 9, |880.

UNITED STATES PATENT ROTARY ENGINE.

SPECIFICATION forming part of Letters Patent No. 234,206, dated November 9, 1880.

Application filed May 31, 1880.

To all whom it may concern:

Be it known that I, WALTER SCOTT, of Richmond, in the county of Richmond and Province of Quebec, Canada, have invented certain new and useful Improvements in Rotary Engines; and I do hereby declare that the following is a full, clear, and exact description of the same.

My invention may be described as consisting in the arrangement, in a cylinder and on the actuating-shalt, of a drum concentric therewith, and carrying in recesses formed in it two or more floats or pistons, these recesses being in depth the full width of the oats, the ends of which enter into circular grooves formed in each of the cylinder-heads eccentrically to the inner drum and outer shell, a portion of the inner surface of the latter being made to correspond with a segment ofthe outer edge of said groove. The cylinder has formed in it longitudinally a bridge or diaphragm extending down through the stand or connection, and forming therein ports, onto a slotted plate forming the top of the steamchest, divided into supply and exhaust chambers, and provided with a valve by which the action ot' the engine can be reversed at will, or steam entirely out oi'. But for full comprehension of the same, reference must be had to the annexed drawings, in which- Figure 1 is a longitudinal sectional elevation of engine; Fig. 2, a transverse vertical section of' same; Fig. 3, a view of interior of cylinder-head; Fig. 4, a view of intermediate or guide plate, and Fig. 5 a plan of top of steam-chest.

Similar letters of reference indicate like parts.

A is the cylinder proper of any rotary engine, of any diameter desired, A' being a bridge or division extending inward till it comes closely in contact with the inner drum, B, to be presently described, and down to the top of the steam-chest C, so as to form two ports, a a'.

The drum B is mounted upon the main shaft D, to which it gives motion, this shaft being preferably, but not necessarily, carried outside either end of the cylinder in standards d.

In the drum B are formed two or more recesses, b, of a depth equal to or slightly greater than the width of the oats or pistons E, which (No model.)

are held in them, and of such a size as to allow these to slide freely in and out, the ends of these loats being carried and their action controlled as will now be described.

In each of the cylinder-heads A2 is formed, as clearly shown in Fig. 3, an annular or circular groove, F, sunk to any depth desired, and arranged eccentricall y to the drum B and cylinder A, part of the inner surface ot' which is, as atf, Fig. 2, cut away from its exact circular form and follows the outer line of groove F.

G Gr are loose journal-boxes, resting in the groove F, and carrying, in openings g g, the journals e of the oats or pistons E.

H H are plates or diaphragms placed between the cylinder-heads A2 and the ends of the drum B, to the latter of which they are bolted, in these being formed grooves h l1., within which are cut slots h' h', serving as guides to the oats or pistons E, which pass through them.

The steam-chest C (shown in Figs. 1,2, and 5) is divided into chambers C' C2, with which communicate, respectively, the supply and exhaust pipes c' c2, the diaphragm C3, forming this division, being at right angles to A'. In the top oi' the steam-chest marked C4 are formed four openings-two, I l', being from the inlet-chamber, and two, K K', from the exhaust, the two openings 1 and K communieatin g with the port a on one side of the bridge A', and the two K' and I' with the port a' on the other side.

L is the valve moving below the top C4 of the steam-chest, and operated, as shown in Fig. l, by means of a screw-rod, L', in it being formed openings M M' N N', M and N being arranged so as to coincide with I and K, and M' and N' with I and K'.

The whole of the parts are put together in any usual and suitable way, and the usual tittings, such as glands, stuffing-boxes, and oilcups, being provided where required.

The operation of my invention is as follows: Steam, being let into the chamber C', passes (when the valve L is so adjusted that the revolution of the shaft will be in the direction shown by the arrow in Fig. 2) up through the openings M and I, then brought to coincide with each other, and the port a, into the cylinder A. It there impinges against that one of the floats E the outer edge of which is in con- IOO tact with the surfncef, driving it forward, and thus gives rotary motion to the drum B and shaft D. As this drum B revolves, the iloats E, passing round in the groove F, are successively forced outward from the drum against the shell A at that portion ot' its inner surface in which, as at f, such inner surface and the outer line ofthe groove F coincide, the length of this seginent being always such that two of the iloats E shall be in contact, therewith at the same time, thus obviating any chance of back-action of steam. By the further revolution of the drum B and its consequent change of position with relation to the groove thc floats E are, after passing beyond the farther point of f, withdrawn within its periphery. The steam, when the port u is made the inlet, passes through the port a ont through the opening K' and coinciding opening N into the exhausbchambcr C2.

The engine is stopped h v moving the slide or valve so as to cut ofi' connection between either of the ports a a' and the supply-chainber C', and its action reversed by further moving the valve so ns to make the openings K in the top oi' the steam-chest and N in the valve coincide, in which case a' will become the discharge-port.

Although a screwed rod is shown as operat4 ing the valve, it must be clearly understood that I do not confine myself to this, as a graduated slide orany other usual device may be substituted therefor. lfdesired, too, the jonrualboxes G (l may be omitted, and the ends ofthe lioats or pistons, minus theirjournals e, enter directly into the groove F; or the guide or groove in which these tioatsor pistons move may be formed by projecting flanges.

1t will bc seen from the above description that a perfectly positive action is secured in either direction without the use ofsprings, and with but one inlet-pipe; that, as there is no cutoff, the motion must be continuous, and that, as the tloats or pistons are in contact with the shell A for but a small proportion of its surface, the friction of working is very much reduced. This surfacefmay be formed with adjustable packing to compensate for wear,

and the bridge A be constructed in the same way and for the same purpose.

Although my invention is primarily intended and specially adapted for rotary steam-engines, it may with great advantage be embodied in water-engines, or, with power applied to the shaft, be used as a pump or meter.

I am aware that a drum or piston revolving on an axle concentric with outer shell and carrying floats working in a cam is not new, and therefore do not claim such, broadly; nor do I claim, in combination with said mechanism,a steam-chest with division corresponding to division in cylinder,

What 1 claim being as follows:

l. I n a rotary engine, the combination of the following elements: a revolving drum or piston holding sliding floats, the ends of which are carried in circular grooves eccentric to said drum, formed inthe ends of an outer shell or cylinder having a part of its inner surface cut away to correspond with a segment of such grooves, all as herein set forth, and for the purposes described.

2. In combination with the circular grooves F, eccentric to the revolving drinn or piston B, loose segmental bushings set in said grooves and carrying the ends of sliding floats E, held in said drum, all as and for the purposes described.

3. 1n a rotary engine divided longitudinally, a steanrchest divided by diaphragm at right angles to division in cylinder into supply and exhaust chambers, and each having two ports or inlets into the cylinder, in combination with a valve having two ports, so as to rotate the piston in either direction, as herein described.

4. In a rotary engine, the combination,with an outer shell or cylinder having formed in its ends circular eccentric grooves carrying the ends of tloats sliding in a circular revolving drum, of grooved and slotted guide-plates H, interposed between the ends of the piston or drum B and outer shell, A, all as set forth.

WALTER SCOTT.

Witnesses B. A. DUN'roN, C. P. CLEVELAND. 

